In recent years, desired functions for an apparatus for mounting an electronic component onto an electronic circuit board have been the speed-up, an improvement in the mounting accuracy of an electronic component, the adaptability to the mounting of multifarious electronic components and an improvement in the quality of an electronic component.
FIG. 10 is a perspective view showing the whole outline configuration of a conventional electronic component mounting apparatus. In FIG. 10, Numerals 101 and 103 denote carrying means for carrying in/out an electronic circuit board 102 and drive means (XY robot) for positioning a head part 105, incorporating a nozzle unit 104 for vacuum-clamping/mounting the electronic component, at any position. Numerals 106, 107 and 108 denote electronic component supply means for supplying the electronic component, nozzle change part for exchanging a nozzle clamped by the nozzle unit 104 depending on packaged component and recognition section for recognizing the clamping posture of electronic component vacuum-clamped by the nozzle.
FIG. 11 is a principally sectional view showing the configuration of a nozzle unit in a conventional electronic component mounting apparatus. In FIG. 11, Numerals 111, 112, 113, 114 and 115 denote a motor for positioning a rotational position, a speed reducer section for improving the rotational precision, a vacuum-clamping nozzle for vacuum-clamping an electronic component, a spring for urging the vacuum-clamping nozzle 113 and a pushing section for transmitting a spring force.
Next, the operation of an electronic component mounting apparatus (FIG. 10) composed of the above members and of a nozzle unit (FIG. 11) will be described.
The electronic circuit board 102 shown in FIG. 10 is carried in the mounting position by means of the carrying means 101. The drive means 103 positions the head section 105 onto the electronic component supply means 106 and after the positioning, the nozzle unit 104 in the head part 105 lowers to vacuum-clamp the electronic component.
Next, after vacuum-clamping the electronic component, the nozzle unit 104 rises and the head part 105 is positioned to the mounting position by the drive means 103. In this move, the vacuum-clamped posture of the electronic component vacuum-clamped by the nozzle unit 104 is recognized in the recognition section 108 and the control section (not shown) performs a correcting computation to correct the position. After the positional correction, the nozzle unit 104 lowers and mounts the electronic component onto the electronic circuits board 102.
In this electronic component mounting apparatus, the speed at which the nozzle unit 104 lowers is constant and cannot be made variable owing to the mechanism. Besides, the urging force at the time of mounting an electronic component is also defined by the spring 114.
As mentioned above, simply under a definite urging force and only at a definite speed at the lowering time of a nozzle, a conventional electronic component mounting apparatus can mount an electronic component. Thus, an improvement in quality such as reduction of damages to an electronic component is required and furthermore, multiple sorts of electronic components at present leads to a demand for inserting a large-sized connector into an electronic circuit board, so that the need for a function able to exert a heavy load has taken place to implement this.